I realized for me to drive my cucv around a lot and for it to be practical I needed an overdrive. I looked at a lot of options such as nv4500, gearvendor, ranger+sm465 but I found the easiest and probably the cheapest swap for me was going to be a 4l80E. Right now I have most of the parts I need to do the swap and I have spent about $875 but I still need to get the rear drive shaft shortened and front one lengthened. I found a deal on facebook marketplace for a 4l80E, np241, and a seized 454 all for $200 so I bought it and then sold the seized big block for $120. I pulled the pan off the 4l80E and it looked really nice inside and the fluid was not burnt so I put a new filter in it and I am planning on using it as is. I also am going to try to use the torque converter that was on it because it is probably a low stall one. Since the 4l80E is electronically controlled I needed a stand alone kit to control it so I got the Painless Performance Perfect Torc kit. I went with the Perfect Torc kit because it was the only kit I found that didn't need a tachometer input from the engine I also had to get a throttle position sensor for the stand alone computer to work so i got a acdelco one made for the 6.2 diesel and it just bolts on the injection pump where the vacuum valve for the th400 shifts used to be. my plan for the trans cooler is to use the stock in-radiator th400 one because i don't plan on hauling heavy trailers in hot weather and it will work out nicely because the 4l80E i have is the earlier one with the cooler line ports both in the front so they should be able to use the th400 cooler lines. In a couple days i’ll commit to pulling the th400 and post more about drive shaft length, the cross member situation, and shift linkage.
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